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Sense transcription through the S region is essential for immunoglobulin class switch recombination.

ABSTRACT: Class switch recombination (CSR) occurs between highly repetitive sequences called switch (S) regions and is initiated by activation-induced cytidine deaminase (AID). CSR is preceded by a bidirectional transcription of S regions but the relative importance of sense and antisense transcription for CSR in vivo is unknown. We generated three mouse lines in which we attempted a premature termination of transcriptional elongation by inserting bidirectional transcription terminators upstream of S?, upstream of S?3 or downstream of S?3 sequences. The data show, at least for S?3, that sense transcriptional elongation across S region is absolutely required for CSR whereas its antisense counterpart is largely dispensable, strongly suggesting that sense transcription is sufficient for AID targeting to both DNA strands.

SUBMITTER: Haddad D

PROVIDER: S-EPMC3102270 | biostudies-literature | 2011 Apr

REPOSITORIES: biostudies-literature

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Sense transcription through the S region is essential for immunoglobulin class switch recombination.

Haddad Dania D Oruc Zéliha Z Puget Nadine N Laviolette-Malirat Nathalie N Philippe Magali M Carrion Claire C Le Bert Marc M Khamlichi Ahmed Amine AA

The EMBO journal 20110304 8

Class switch recombination (CSR) occurs between highly repetitive sequences called switch (S) regions and is initiated by activation-induced cytidine deaminase (AID). CSR is preceded by a bidirectional transcription of S regions but the relative importance of sense and antisense transcription for CSR in vivo is unknown. We generated three mouse lines in which we attempted a premature termination of transcriptional elongation by inserting bidirectional transcription terminators upstream of Sμ, up ...[more]

PMID: 21378751

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